1. Field of the Invention
The present invention relates to a solid state image sensor, and more specifically to a solid state image sensor having a photoelectric converting element constituted of a buried photodiode.
2. Description of Related Art
A typical solid state image sensor is such that a signal electric charge accumulated in a photoelectric conversion region is transferred to a charge transfer region through a gate region. However, the conventional solid state image sensor has a disadvantage in which a portion of the signal charge to be read from the photoelectric conversion region still remains in the photoelectric conversion region. This means that, at the time of the signal charge reading, all of the signal charge cannot be read out or transferred from the photoelectric conversion region to the charge transfer region, and therefore, an afterimage occurs.